Photographic illuminating means



April 15, 1958 BRANDT 2,831,104

PHOTOGRAPHIC ILLUMINATING MEANS Filed Jan. 30, 1956 2 Sheets-Sheet 1 BYW April 15, 1958 R. J. BRANDT PHOTOGRAPHIC ILLUMINATING MEANS 2Sheets-Sheet 2 Filed Jan. 30, 1956 United rates PHOTOGRAPHIC HJLUMINATING MEANS Robert Jay Brandt, Hollywood, Calif. Application January 30,1956, Serial No. 562,087

3 Claims. ((11. 240-13) tion of pleasing pictures by lighting up theshadows so that they will not be too dark. The fill light should be adiffused light without glare, but with sutficient intensity to balancethe lighting and avoid undesirable shadows such as those produced aroundthe subjects chin, ears, and eyelashes, by harsh lighting. This isespecially desirable in close-ups.

A properly designed fill light will permit the taking of close-upswithout the subjects face appearing flat and lacking in roundness, whileat the same time avoiding dark shadows and harsh lighting effects.Furthermore, for television and motion picture color photographypurposes, the fill light should be a white light so that the pictureswill not have a red or other colored overcast. The fill light should bedesigned to make emcient use of the energy from the light source toproduce light of maximum intensity without over-heating and shorteningof the life of the light source.

Accordingly, it is an important object of my invention to provide asource of illumination for efliciently producing diffused light forcolor and black and white photography which will serve as a fill lightfor lighting up undesirable shadows without destroying the high lighteffects produced by the key lights.

Another object is to provide an improved fill light for the eflicientproduction of diffused white light sub stantially free of directradiation and glare so that pleasing pictures in color can be obtainedwithout the production of undesirable red or other colored overcasts.

A further object is to provide a fill light of economical design for theeflicient production of diffused white light of maximum intensitywithout the production of overheating and consequent shortening of thelife of the light source.

Additional objects will become apparent from the following description.

In general terms, my invention comprehends a source of illuminationsuitable as a fill light in photography comprising a light sourcemounted adjacent a reflector, a mask positioned in front of the lightsource to prevent the transmission of direct rays from the source to thesubject, and light diffusion or shield means positioned in the lightassembly to prevent the emission of direct rays from the light sourceand produce diffused light of maximum intensity without glare.

When an electric light source is employed, the reflecting surface of thereflector is painted or coated with a suitable material for absorbingthe infra-red radiation of the light source, and producing reflectedwhite light. The reflecting surface preferably is made conical in shaperather than parabolical so that parallel rays of light are Patented Apr.15, 1958 not produced but instead, rays of light having different anglesof reflection and resulting in a diffused light, are produced. The maskemployed preferably is opaque, and is positioned in front of the lightsource to mask only that portion of the direct rays which would betransmitted centrally of the front of the light assembly.

A skirt or shield preferably is attached to the periphery of the base ofthe reflector to diffuse or shield the direct rays transmitted from thelight source which pass between the reflecting surface of the reflectorand the mask, so that these rays will be diffused by the skirt orreflected within the light source by the shield. Additional diffusion oflight is produced by a diffusion means positioned in the face of thelight source. This diffusion means preferably is a spun glass diffusionpane.

A more detailed description of specific embodiments of my invention isgiven with reference to the drawings, wherein:

Figure l is a sectional elevational view taken on the line 1-1 of Figure2 showing one embodiment of the fill light mounted for overheadillumination as in the case of its use on a motion picture or televisionstudio set;

Figure 2 is a bottom view of the light shown in Figure 1 drawn to asomewhat reduced scale and showing the face of the light assembly;

Figure 3 is a plan view showing a ring of the type used in the light ofFigure 1 for holding and shaping a diffusion cloth skirt drawn to astill more reduced scale;

Figure 4 is a front elevational view drawn to a smaller scale thanFigure 2 showing another embodiment of the fill light of my inventionused as a stand lamp;

Figure 5 is a sectional elevational view taken on the line 5-5 of Figure4 drawn to a somewhat enlarged scale; and

Figure 6 is a fragmentary cross-sectional view drawn to an enlargedscale and taken along the line 6-6 of Figure 5.

In the specific embodiment of my invention shown in Figures 1 to 3 ofthe drawings, an electric light bulb It} is mounted in a socket 11. Thesocket in turn is mounted on the inside of a conical reflector 12 by abracket 13. The bracket 13 may be bolted or brazed to the inside surfaceof reflector 12 in a manner to centrally position light bulb 10 insidethe reflector. At-

tached to the bracket 13 is an arm 14 connected to a masking panel 16constructed of an opaque material such as a metal, for example. Themasking panel 16 preferably is dished as shown and is oriented in frontof the light 10 to prevent direct rays thereof from being transmittedfrom the fill light assembly. The surface of the masking panel 16adjacent bulb 10 may be given a mirror finish to reflect the maskeddirect rays of light backward to the surface of reflector 12.

The inner surface of the reflector cone 12 is treated in a manner toabsorb the infra-red radiation transmitted thereto from the light bulb10. The surface of the reflector may be treated in any of various waysknown in the art to accomplish the absorption of infra-red radiation. Apreferred method of making this treatment is to paint the reflectingsurface of the cone 12 with an infra-red radiation absorbing paint, sothat the light reflected from the surface of the cone 12 will becolorcorrected to reflect white light having substantially the samecolor composition as sunlight.

T he cone 12, as well as other metallic parts of the light assembly, canbe made of deep drawn steel. Other metals can, however, be usedsatisfactorily.

The bulb It) has been shown mounted in the reflector 12 with its majoraxis at right angles to' the axis of the conical reflector. Althoughthis position is shown, it will be understood that I can mount bulb sothat its major axis coincides with the axis of reflector 12.

The reflector 12 is provided on its outside with cooling andre-inforcing channels 17 shown in detail in Figure 6. The channelsextend from the peak of the reflector toward its base. The reflector 12is provided with rows of apertures 18 aligned with the channels 17, andcommunicating with their interiors. The sides of the channels 17 areprovided with rows of apertures 19 communicating with the atmosphere.This arrangement permits convection currents of hot air to flow from theinside of reflector 12 through apertures 18 and 19 into the atmosphere.In

- this manner, the inside surface of the reflector 12 is cooled by theconvection currents without the escape of appreciable amounts of lightthrough the walls of the reflector, and to the rear of the fill lightassembly.

Two or more channels 17 are attached to the outside of reflector 12.Each of the channels is provided with a hanging eyelet 21. The filllight assembly is suspended overhead by two or more cables 22 attachedto the hanging eyelets 21, as best shown in Figure 1. At the peak of theconical reflector 12 is attached another cable or chain, as indicated at23, for tilting the fill light at an angle to the horizontal, asdesired. In this manner the intensity of the fill light can be balancedor varied in different areas of the set.

A snap switch 24 is connected to a source of electrical energy (notshown) and to the socket 121. The switch 24 is suitably mounted on abracket 26 fastened to the outside of reflector 12 by any suitablemeans.

A skirt 27 of light diffusing cloth is mounted around the periphery ofthe base of reflector 12 to extend vertically downward in the form of acylindrical section. Seams 28 are sewn at the upper and lower ends ofthe skirt 27 as indicated. A spring ring 29 having its ends overlappingat 31 is threaded into each of the seams 28 of the skirt. The springrings 29 serve to hold the cloth tightly in the form of a cylindricalsection by spreading the cloth outwardly through their springiness andby weighting it downwardly at the lower seam 28. The skirt 27 isfastened to the peripehry of the base of the reflector 12 by three clips32 fastened to a flange 35. Flange 35 is made integral with the conicalreflector 12.

The skirt 27 is designed to prevent the passage of direct rays of lightfrom lamp bulb 10 through the face of the light assembly. For thisreason, the skirt 27 is made of cloth having a coarse mesh such thatlight striking it will be diffused and emitted from the outside surfaceof the cloth as a soft diflt'used light free of glare and direct rays oflight. Batiste cloth has been found to be satisfactory for this purpose,but other kinds and types of loose mesh cloth made of natural orsynthetic fibers, or metallic screens, can be used for this purpose.

The length of the batiste cloth skirt or other cloth skirt 27 isdesigned and positioned in relationship to the design and positioning ofthe masking panel 16 and the positioning of the lamp bulb 10 so that alldownwardly directed rays from lamp bulb 10, which are not masked by themask 16, and not reflected by the conical reflector 12, will strike thevertical inside wall of the skirt 27 and be diffused before beingtransmitted from the light assembly.

, Inside the skirt 2'7, and preferably approximately in the planepassing through the lower end of the skirt, is mounted a diffuser pane33. The pane 33 preferably is in the form of a flat disc and iscentrally. mounted inside the skirt 27 in alignment with the centralaxis of reflector cone 12 and the centers of lamp bulb 1t and maskingpanel 16. The puropse of the diffusor pane 33 is to additionally diffuselight reflected from the surface of reflector 12 to thus additionallyinsure against glare, and uneven intensity in the light transmitted fromthe light assembly.

The use of a spun glass disc as pane 33 has been found to be verysatisfactory. The spun glass disc permits the subject to look directlyinto the front of the fill light without squinting because the glare hasbeen completely removed from the light rays projected from the lightassembly. Other materials may be used instead of the spun glass disc inthe diffusor pane 33. Such materials include ground glass, translucentplastics and gels, as well as other diflusing materials known in theart.

The diffuser pane 33 is mounted in a frame 34 known as a jelly frame.-The frame is made up of four rings, two inner rings 36 and two outerrings 37 of somewhat greater diameter than the inner rings. The innerrings 36 are of approximately the same diameter and are spaced one abovethe diffuser pane 33 and the otherbelow the pane. The edge of thediffusor pane abuts the outer rings 37 as they are positioned one abovethe other. The annular edge of the pane 33 is beveled to fit into theannular crevice formed by the abutting outer rings 37, as indicated.

The inner rings 36 and the outer rings 37, with the dir'fusor pane 33mounted in the rings as shown are held together in a diffuser paneassembly 34 by three clips 38. The cllps38 tightly engage the upperinner ring of the pair of inner rings 36, pass tightly around the upperouter ring of the pair of rings 37, and tightly engage the lower outerring of the rings 37, as best shown in Figure 1.

The diffuser pane assembly 34 is held in position inside skirt 27 bythree chains 33. The chains 39 are fastened to the diflusor assembly 34in any convenient manner, such as by hooks 41 passing around the upperouter ring of the pair of outer rings 37, as shown in Figure l. Theupper ends of the chains 39 may be attached to the light assembly in anyconvenient manner, such as by means of clips 42 engaging the upper ring29 in the upper seam 28 of the skirt 27.

In mounting the light assembly shown in Figures 1 to 3, the lightassembly is hoisted by cables 22 to the proper overhead elevation on atelevision or motion picture set, for example. If it is desired tochange the vertical direction of the light striking the set, the lightcan be tilted out of the horizontal plane by applying a tension to thechain connected to the apex of the conical reflector 12 at 23. Byapplying the proper degree of tension at 23, at an angle to thevertical, the light assembly can be tilted so that the general directionof the light projected from the assembly will be adjusted to the desireddegree.

When an overhead battery of lights is used, a fine balance of thelighting can be accomplished by snapping oil some of the lights at asnap switch 24. In this manner, a very satisfactory fill light of whitequality, the desired degree of intensity and balance, as well asdirection, can be projected on-a motion'picture or television studio setfor both black and white, as well as color photography.

Pleasing true color pictures are produced by using the till lightsproduced by the light assembly described above. Especially satisfactoryclose-ups are made in black and white as well as in color. Theseclose-ups contain well-lighted faces free of unpleasant and "distractingshadows such as are frequently noted at the chin, ears, around the eyes,under the nose, and on the cheeks when prior art, harsh lighting isused. These effects of harsh ighting have been eliminated by using thelight assembiy described above for both color and black and whitetelevision and motion pictures, without destroying or burning up thehigh lights produced by the key light effects.

The light assembly can be made in various sizes having diameters at theperiphery of the base of the reflector cone i2 ranging from about 12inches to about 39 inches, for example. in the larger sized lamp, a 5kilowatt bipost light bulb 13 is used, whereas in the smaller-sizedlamps, a 2 kitowatt bulb is used. It has been found that a lightproducing about 250 foot candles at 20 to 25 feet therefrom will be asatisfactory fill light when used with the proper key lighting.

When using the larger 39 inch size light, the use of a skirt 13 incheshigh and a masking panel 16 having an overall diameter of 11 inches hasbeen found to give satisfactory results. The diameter of the diffusorpane 33, in a light assembly of this size may vary from about 39 inchesto about 29 inches, or less, depending on the results desired.

Because of the high degree of cfliciency of the light assembly describedabove, and the relatively cool operation of the light, the life of thebulbs 18 has been greatly increased as compared to the relatively shortlife of the bulb in prior art lights. The light bulb replacement andrepair costs of the present light assembly have been reduced to a pointwhere the use of a relatively large number of such fill lights isfeasible on a motion picture or television set.

In the embodiment of my invention shown in Figures 4 and 5, the skirt 27has been replaced by a shield 43 in the general shape of a cylindricalsection. The inner end of the shield 43 is formed into an inwardlyextending flange 44 adapted to fit snugly over the peripheral flange 35of the reflector 12. The shield 4-3 is attached to the reflector 12 atthe flanges 3S and 34 by clamps Clamps 46 are provided with threadedholes for threaded engagement with wing bolts 47. The wing bolts 47 passthrough apertures in the side wall of the shield 43, as best shown inFigure 5.

In this embodiment, the diffuser pane 48 preferably is made of a largerdiameter than that of dififusor pane 33 in the overhead embodiment ofFigures 1 to 3. The diffuser pane 48 can be mounted in a jelly frame ofthe type described in connection with the mounting of pane 33. Difl'usorpane 48 requires a larger frame. Also, as shown best in Figure 5, thejelly frame is fastened to the rolled end 49 of shield 43 by clips 51.

The light assembly of the embodiment of Figures 4 and 5 is mounted in astand or tripod 52, as best shown in Figure 4. The light assemblypreferably is mounted for rotation about a horizontal axis, and about avertical axis, as well as for adjustment of the angles of these axes bythe tripod, so that the light can be directed in any desired direction,as will readily be understood.

In use of the stand lamp of Figures 4 and 5, the shield 43 serves toprevent the formation of a halo of light in the projected fill lightproduced by this embodiment of my invention. The design and therelationship of the light bulb and the masking panel 16 is again suchthat no direct rays of the light can pass from the light bulb throughthe diffusor pane 48. The height of the shield 43 is made suificient toavoid the transmission of any direct rays of light beyond the edge ofthe masking panel 16 and through the diffusor pane 48. This prevents theformation of an undesirable halo of light in the projected illumination.

In other respects, the construction and operation, as well as theresults and advantages of the fill light of Figures 4 and 5 are similarto those described in connection with the embodiment of my inventiondescribed above in connection with Figures 1 to 3.

Although my invention has been described above as applied primarily toprovide fill light illumination for television and motion picturephotography, it will be understood that it is applicable as a source ofillumination for numerous other purposes where a soft, difiused light ofhigh intensity, casting no, or insignificant shadows, is desired. Anexample of such other applications, requiring illumination of suchcharacter, is found in an operan'ng room. The careful and precise workof the surgeon demands illumination which lights up the internal organsof the body without casting dark shadows, and without producing glare byreflections from the surfaces of the viscera. Another example is use indentists offices where the same advantages contribute to the convenienceand efliciency of the attending dentist and technician. Such lightingis, of course, also advantageous when color television is employed inthe operating room as a teaching aid for students of surgery.

While I have herein shown and described my inven tion in what I haveconceived to be the most practical and preferred embodiments, it isrecognized that departures may be made therefrom within the scope of myinvention, which is not to be limited to the details disclosed herein,but is to be accorded the full scope of the claims so as to embrace anyand all equivalent structures.

Having described by invention, what I claim as new and desire to secureby Letters Patent is:

l. A source of illumination comprising a reflector means of generallyconical shape, an electric light source mounted in front of thereflector means for transmission of light from the source to thereflector means, the reflector means being provided with a surface whichabsorbs infra-red light and reflects white light to the front of thelight source, shield means projecting from the reflector means, diflusormeans positioned in front of the reflector means for diifusing rays oflight reflected from the reflector means, and mask means positioned infront of the light source for masking direct rays of light emittedtherefrom, the mask means being positioned relative to the shield meansand the light source for prevention of transmission of direct rays oflight from the light source beyond the shield means.

2. A source of illumination comprising a reflector means of generallyconical shape, an electric light source mounted in front of thereflector means for transmission of light from the source to thereflector means, a reflecting surface on the reflector means whichabsorbs infrared light and reflects white light from the reflectormeans, a light-diifusing skirt means extending from the reflector meansfor diffusing direct rays of light emitted from the light source,diffuser means comprising a spun glass pane positioned in front of thereflector means for diffusing rays of light reflected from the reflectormeans, and mask means comprising an opaque panel positioned in front ofthe light source for masking direct rays of light emitted therefrom, themask means being positioned relative to the skirt means and the lightsource for prevention of transmission of direct rays of light from thelight source beyond the shield means.

3. A fill light comprising a conical reflector, a reflecting surfacepainted on the inside of the reflector with paint that absorbs infra-redlight and reflects white light, an electric light source mountedcentrally inside the reflector for transmission of light from the sourceto the reflecting surface and for the reflection of diffused white lightfrom the reflecting surface, a skirt of light-diifusing cloth extendingfrom the base of the reflector for diffusing direct rays of lightemitted from the light source and trans- References Cited in the file ofthis patent UNITED STATES PATENTS 2,280,402 Greppin Apr. 21, 19422,433,982 Clarkson et a1. Jan. 6, 1948 2,469,412 Roebken May 10, 19492,494,058 Ries et a1. Ian. 10, 1950 2,688,271 Gretener Sept. 7, 1954FOREIGN PATENTS 234,530 Great Britain June 2, 1925

